1. Field
An aspect of the present invention relates to a battery pack.
2. Description of the Related Art
Secondary batteries are rechargeable and can be repeatedly used. Secondary batteries may be implemented as a battery cell used for portable small-sized electronic devices such as a cellular phone, a desktop computer, a laptop computer, a camera, or camcorder. Alternatively, secondary batteries may be implemented as a battery pack including a plurality of battery cells, used as a power source for driving motors of a high-power hybrid electric vehicle (HEV), an electric vehicle (EV), and the like.
Batteries used in a hybrid electric vehicle (HEV), etc. should implement high power and high capacity. For this reason, a battery pack is configured as one unit using a plurality of batteries, and a plurality of battery packs are electrically connected in series or parallel, so that the connected battery packs are operated as a high-capacity and high-power source.
Because of characteristics of the HEV, the battery pack should be fixed so as to not be arbitrarily separated due to vibration, etc. The battery pack may be fixed to a bottom of the HEV in various manners, in consideration of a cooling effect, etc. The cooling efficiency of HEV, PHEV and EV batteries depends on contact with a cooling member. Particularly, when a contact pressure between the cooling member and cells constituting the battery pack are different, the variation in temperature between the cells may be increased. Therefore, a structure of a battery pack is desirable in which a sufficient and substantially uniform pressure can be applied to a cooling member and cells.